The present invention relates to a fuel filter system, especially a system for filtering diesel fuel, and to a method of operating such a fuel filter system.
Published German patent application no. DE 101 38 695 discloses a device for removing water from a fuel system. The fuel system has a filter element on which water is deposited. The deposited water collects in a collecting space. Beneath the collecting space there is a catchment area, with a membrane provided between the collecting space and the catchment area. The membrane is constructed so that only ultrapure water can pass through it. The membrane is not permeable to fuel molecules. A water sensor situated in the collecting space is connected to a valve provided in the catchment area.